1. Technical Field
The present disclosure relates to a map production method, a mobile robot, and a map production system.
2. Description of the Related Art
Robot technology has been developed for the purpose of exploration in an environment which a person cannot enter or automation for working in place of a person. Mobile robots which do cleaning while moving inside a house or the like have been on sale in recent years. Mobile robots are being introduced into a familiar region of human life. Such a mobile robot itself needs to accurately recognize a self position and posture and a surrounding environment in order to determine a movement route.
As a technique for estimating a self position and producing a map, simultaneous localization and mapping (SLAM) technology is known. SLAM technology uses an internal sensor which is a sensor a mobile robot includes and detects the amount of change in position and posture and an external sensor which is a sensor the mobile robot includes and captures relative information to a surrounding environment. With use of these sensors, SLAM technology can create a map of surroundings in parallel with estimation of a self position and posture without giving, in advance, map information to the mobile robot.
SLAM technology reiterates mainly two processes. A first process is to predict a current position and posture of a mobile robot from information acquired by an internal sensor and predict relative information to a surrounding environment of the mobile robot on the basis of the predicted position and posture and previously created map information. A second process is to calculate likelihood on the basis of the relative information predicted in the first process and relative information to an actual surrounding environment obtained by an external sensor. The weight of the reliability of the internal sensor and that of the external sensor are determined from the calculated likelihood, and the current self position and posture of the mobile robot and the map information are updated.
A method for implementing autonomous movement in an environment with a change in map is disclosed in Japanese Unexamined Patent Application Publication No. 2011-108084. An autonomous running car disclosed in Japanese Unexamined Patent Application Publication No. 2011-108084 calculates the possibility of running of the autonomous running car itself by estimating a self position and posture with respect to an object using a laser beam or a sensor of, for example, a camera. The autonomous running car disclosed in Japanese Unexamined Patent Application Publication No. 2011-108084 judges the possibility of running of an autonomous running car on the basis of the calculated possibility of running of the autonomous running car itself and the possibility of running obtained by a flight vehicle.